Gediminas Vaičiūnas

Determination of the dynamic characteristics of freight wagons with various bogie

In most cases, dynamic characteristics determine the wagon maintenance cycle, traffic safety, reliability and durability performance. The main dynamic indicators include the vertical Kvd and horizontal Khd dynamic coefficients as well as the stability coefficient Ks, which determines the wheel flange resistance to derailment. The article compares dynamic indications for three different types of bogies. There were no tangible differences observed for all the three different types of bogies running at a speed of 40 to 120 km/h on a direct tangent rail section. Nevertheless, there is a realistic potential to improve the dynamic indicators of a freight wagon by rationalising suspension unit parameters.

Determining Major Factors Causing the Wear of Wheelset Tyres

Graphical representation of laws governing the abrasion of locomotive wheelsets shows different distribution of values obtained for oiled and not oiled wheelset tyres. When wheelset tyres are oiled, the much higher deviation of abrasion values can be observed. This allows us to assume that oiling is more important for reducing the wear of not heavily loaded wheelset tyres.

Analysis of Passenger Rolling Stock Faults and its Statistics in Lithuania

Abstract Performed data analysis aims to determine the number of rolling stock breakdowns and how it depends on rolling stock age, the number of passengers and operations. The mathematical model, stated below, analyses correlation between passenger fleet upgrade intensity and the number of faults. When planning to buy some new rolling stock (3÷6 wagons electric or diesel trains) while using this model, the number of faults can be predicted up to five years.

A Survey of Methods Used for Assessing the Performance of Diesel Locomotives

Abstract The present paper is aimed at evaluating the methods used for determining the performance of Diesel locomotives. Therefore, two main approaches to assessing the locomotive performance can be distinguished: a method based on individual indicators; a method based on an integrated indicator. The analysis of the available methods for complex evaluation of the locomotive condition has shown that overall performance of the locomotive can be described by a dimensionless indicator. In determining the state of Diesel locomotives, researchers rely on the criteria commonly used in assessing the performance of any machine. They are as follows: technical, economical, functional (operational).

Investigating the dynamics of passenger rolling stock deterioration

Abstract One of the major economic criteria is associated with the growth of maintenance costs of old rail vehicles. The research aims to determine the ageing criteria of passenger rolling stock, which could take into account fuel, diesel oil and repair costs. Therefore, economic criteria based on the above costs are generated and their comparative analysis is made. The research object is Vilnius locomotive depot.

Evaluation of the Influence of a Rail Vehicle Running with Wheel-flat on the Railway Track

Abstract The railway transport network is currently in a quite big expansion. Therefore, railway tracks are modernized and the attention is given also on the technical state of rail vehicles, which operate on them. However, it may happen that the wheel surface is damaged. One of the most common reasons of wheel damage is too much braking, which results to the wheel-flat formation. This article is focused on the evaluation of the influence of a rail vehicle running on the railway track, which a wheel is damaged by the wheel-flat. Investigation of these negative effects was performed by means of simulation computations. As evaluating parameters, values of the wheel force in the contact of the rail and wheel with a flat where observed.